Explosive devices used for penetrating pressurized gas containers, today in combination with inflatable rescue equipment, such as disclosed in the published WO 2008/013489, are rather bulky and have a complex design with many different components.
Other penetrating devices are based on one or more moving components that mechanically penetrate the pressurized gas containers. This requires a complex design in order to ensure proper functionality and as a result of the complex design, the weight is normally rather high.
For instance, U.S. Pat. No. 5,413,247 by Glasa, describes a system wherein a sharp object is mechanically moved using a spring loaded force. Alternatively, the force needed to advance the sharp object could be provided by a pyrotechnical charge. In both cases the dimension of the sharp object will determine the size of the hole.
In addition, a German utility model DE 296 06 782 U1 describes an automatic rescue device for sea and air transport including a water sensor. A puncture device is briefly discussed, which is used to open a pressurized gas cylinder. The puncture device could be implemented as a chemical reaction unit, and more specifically be constructed as a pyrotechnical detonator situated outside a gas management device through which the gas flow when the gas cylinder is opened. A hollow needle could also be used for manually puncturing the closure of the gas cylinder if needed.
The major disadvantage with prior art devices is that they are bulky and have a complex design, with or without moving parts. When implementing an explosive device in a system, e.g. for penetrating a gas cylinder or for igniting a charge in military applications, space is a crucial limitation, and there still exists a need to reduce the size of present explosive devises.